Most Catastrophic Volcanic Eruptions Ever

From 1900 to the present date, these volcanic eruptions have affected more people than any others.

Mount Pinatubo on the Filipino island of Luzon erupting in June of 1991.

People are affected by volcanic eruptions in many different ways. While some of these outcomes are, surprisingly, good ones, others are just plain catastrophic. We look at the volcanic eruptions whose reaches extended into the lives of the highest numbers of people in the 20th Century and New Millennium thus far.

The ‘bad’ ways in which volcanoes affect people are usually obvious. They can include buildings, houses, fields and roads becoming unusable as they are covered beneath mounds of ash. Also, in cases where the ash and smoke permeate the atmosphere, it can become extremely hard for people to breathe, and consequently triggering a number life-threatening conditions upon those affected. Although lava flows are too slow to run over people, they can definitely run over roads, houses, and other such components of infrastructure, and ultimately destroy them completely. While evacuations would seem an obvious option to pursue, it is often unfeasible to evacuate large populations, especially when there is little warning prior to an eruption. It is aspects such as these that make volcanoes so destructive. On the other hand, undersea volcanoes can build new islands and land mass, and fertilize soils as they deposit ash and nitrogen-rich components alike. That said, we take a look at the volcanoes that have directly affected the most people, mostly negatively, since 1900.

The Volcano Affecting the Largest Number of People on Record

EM-DAT took up an initiative recently to determine the numbers of people affected by individual volcanic eruptions based on global records from 1900 to 2015. The statistics presented within this database are truly shocking. The most people affected by a single volcanic eruption occurred in the Philippines on the 9th of June in 1991. That particular volcano alone affected approximately 1,036,065 people in the area. The eruption is known as the ‘Mount Pinatubo Volcano’, and it occurred after the volcano had remained dormant for nearly 400 years. It was known to be active at some point in the past 1,000 years, and was even the site of a failed geothermal development. The mountain was considered the home of ‘Apo Namalyari’, a divine entity known as the “Great Provider and Protector” by the ‘Aetas’ people who lived there. It caused such immense destruction due to a convergence of delayed evacuation efforts, giant mudflows, high-speed avalanches of gas and hot ash, and the spread of a cloud of volcanic ash hundreds of miles across.

Other Far-Reaching Volcanic Events

Coming in second we have a volcano that erupted in Nicaragua on April 9th , 1992 which impacted the lives of approximately 300,075 people. An estimated 33,013 people were affected by a volcanic eruption that occurred in Ecuador on the 14th of August, 2006. Two volcanic eruptions that occurred in Indonesia in 1969 and on April 5th, 1982 affected the lives of nearly 250,000 and 300,000 people respectively.

Final Takeaways

Volcanoes can cause a lot of destruction. With the potential to destroy everything that comes in its way, a volcanic eruption can prove disastrous for local residents of their surrounding areas, as has been proven by EM-DAT statistics. The most significant factors causing such high numbers of casualties to be incurred include the population density of the surrounding area, and the scope and scale of the volcanic eruption itself. Also, as can be seen from the countries afflicted in the data, living in island or coastal areas seems to increase risk, as such places are likely near faults or rifts, and therefore more susceptible to seismic and volcanic events.